1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_CODE_NMETHOD_HPP
26 #define SHARE_CODE_NMETHOD_HPP
27
28 #include "code/codeBlob.hpp"
29 #include "code/pcDesc.hpp"
30 #include "oops/metadata.hpp"
31 #include "oops/method.hpp"
32
33 class AbstractCompiler;
34 class CompiledDirectCall;
35 class CompiledIC;
36 class CompiledICData;
37 class CompileTask;
38 class DepChange;
39 class Dependencies;
40 class DirectiveSet;
41 class DebugInformationRecorder;
42 class ExceptionHandlerTable;
43 class ImplicitExceptionTable;
44 class JvmtiThreadState;
45 class MetadataClosure;
46 class NativeCallWrapper;
47 class OopIterateClosure;
48 class SCCReader;
49 class SCCEntry;
50 class ScopeDesc;
51 class xmlStream;
52
53 // This class is used internally by nmethods, to cache
54 // exception/pc/handler information.
55
56 class ExceptionCache : public CHeapObj<mtCode> {
57 friend class VMStructs;
58 private:
59 enum { cache_size = 16 };
60 Klass* _exception_type;
61 address _pc[cache_size];
62 address _handler[cache_size];
63 volatile int _count;
64 ExceptionCache* volatile _next;
65 ExceptionCache* _purge_list_next;
66
67 inline address pc_at(int index);
68 void set_pc_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _pc[index] = a; }
69
70 inline address handler_at(int index);
71 void set_handler_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _handler[index] = a; }
72
73 inline int count();
74 // increment_count is only called under lock, but there may be concurrent readers.
75 void increment_count();
76
77 public:
78
79 ExceptionCache(Handle exception, address pc, address handler);
80
81 Klass* exception_type() { return _exception_type; }
82 ExceptionCache* next();
83 void set_next(ExceptionCache *ec);
84 ExceptionCache* purge_list_next() { return _purge_list_next; }
85 void set_purge_list_next(ExceptionCache *ec) { _purge_list_next = ec; }
86
87 address match(Handle exception, address pc);
88 bool match_exception_with_space(Handle exception) ;
89 address test_address(address addr);
90 bool add_address_and_handler(address addr, address handler) ;
91 };
92
93 // cache pc descs found in earlier inquiries
94 class PcDescCache {
95 friend class VMStructs;
96 private:
97 enum { cache_size = 4 };
98 // The array elements MUST be volatile! Several threads may modify
99 // and read from the cache concurrently. find_pc_desc_internal has
100 // returned wrong results. C++ compiler (namely xlC12) may duplicate
101 // C++ field accesses if the elements are not volatile.
102 typedef PcDesc* PcDescPtr;
103 volatile PcDescPtr _pc_descs[cache_size]; // last cache_size pc_descs found
104 public:
105 PcDescCache() { debug_only(_pc_descs[0] = nullptr); }
106 void init_to(PcDesc* initial_pc_desc);
107 PcDesc* find_pc_desc(int pc_offset, bool approximate);
108 void add_pc_desc(PcDesc* pc_desc);
109 PcDesc* last_pc_desc() { return _pc_descs[0]; }
110 };
111
112 class PcDescContainer : public CHeapObj<mtCode> {
113 private:
114 PcDescCache _pc_desc_cache;
115 public:
116 PcDescContainer(PcDesc* initial_pc_desc) { _pc_desc_cache.init_to(initial_pc_desc); }
117
118 PcDesc* find_pc_desc_internal(address pc, bool approximate, address code_begin,
119 PcDesc* lower, PcDesc* upper);
120
121 PcDesc* find_pc_desc(address pc, bool approximate, address code_begin, PcDesc* lower, PcDesc* upper)
122 #ifdef PRODUCT
123 {
124 PcDesc* desc = _pc_desc_cache.last_pc_desc();
125 assert(desc != nullptr, "PcDesc cache should be initialized already");
126 if (desc->pc_offset() == (pc - code_begin)) {
127 // Cached value matched
128 return desc;
129 }
130 return find_pc_desc_internal(pc, approximate, code_begin, lower, upper);
131 }
132 #endif
133 ;
134 };
135
136 // nmethods (native methods) are the compiled code versions of Java methods.
137 //
138 // An nmethod contains:
139 // - Header (the nmethod structure)
140 // - Constant part (doubles, longs and floats used in nmethod)
141 // - Code part:
142 // - Code body
143 // - Exception handler
144 // - Stub code
145 // - OOP table
146 //
147 // As a CodeBlob, an nmethod references [mutable data] allocated on the C heap:
148 // - CodeBlob relocation data
149 // - Metainfo
150 // - JVMCI data
151 //
152 // An nmethod references [immutable data] allocated on C heap:
153 // - Dependency assertions data
154 // - Implicit null table array
155 // - Handler entry point array
156 // - Debugging information:
157 // - Scopes data array
158 // - Scopes pcs array
159 // - JVMCI speculations array
160
161 #if INCLUDE_JVMCI
162 class FailedSpeculation;
163 class JVMCINMethodData;
164 #endif
165
166 class nmethod : public CodeBlob {
167 friend class VMStructs;
168 friend class JVMCIVMStructs;
169 friend class CodeCache; // scavengable oops
170 friend class JVMCINMethodData;
171 friend class DeoptimizationScope;
172
173 private:
174
175 // Used to track in which deoptimize handshake this method will be deoptimized.
176 uint64_t _deoptimization_generation;
177
178 uint64_t _gc_epoch;
179
180 // Profiling counter used to figure out the hottest nmethods to record into CDS
181 volatile uint64_t _method_profiling_count;
182
183 Method* _method;
184
185 // To reduce header size union fields which usages do not overlap.
186 union {
187 // To support simple linked-list chaining of nmethods:
188 nmethod* _osr_link; // from InstanceKlass::osr_nmethods_head
189 struct {
190 // These are used for compiled synchronized native methods to
191 // locate the owner and stack slot for the BasicLock. They are
192 // needed because there is no debug information for compiled native
193 // wrappers and the oop maps are insufficient to allow
194 // frame::retrieve_receiver() to work. Currently they are expected
195 // to be byte offsets from the Java stack pointer for maximum code
196 // sharing between platforms. JVMTI's GetLocalInstance() uses these
197 // offsets to find the receiver for non-static native wrapper frames.
198 ByteSize _native_receiver_sp_offset;
199 ByteSize _native_basic_lock_sp_offset;
200 };
201 };
202
203 // nmethod's read-only data
204 address _immutable_data;
205
206 PcDescContainer* _pc_desc_container;
207 ExceptionCache* volatile _exception_cache;
208
209 void* _gc_data;
210
211 struct oops_do_mark_link; // Opaque data type.
212 static nmethod* volatile _oops_do_mark_nmethods;
213 oops_do_mark_link* volatile _oops_do_mark_link;
214
215 CompiledICData* _compiled_ic_data;
216
217 // offsets for entry points
218 address _osr_entry_point; // entry point for on stack replacement
219 uint16_t _entry_offset; // entry point with class check
220 uint16_t _verified_entry_offset; // entry point without class check
221 int _entry_bci; // != InvocationEntryBci if this nmethod is an on-stack replacement method
222 int _immutable_data_size;
223
224 // _consts_offset == _content_offset because SECT_CONSTS is first in code buffer
225
226 int _skipped_instructions_size;
227
228 int _stub_offset;
229
230 // Offsets for different stubs section parts
231 int _exception_offset;
232 // All deoptee's will resume execution at this location described by
233 // this offset.
234 int _deopt_handler_offset;
235 // All deoptee's at a MethodHandle call site will resume execution
236 // at this location described by this offset.
237 int _deopt_mh_handler_offset;
238 // Offset (from insts_end) of the unwind handler if it exists
239 int16_t _unwind_handler_offset;
240 // Number of arguments passed on the stack
241 uint16_t _num_stack_arg_slots;
242
243 uint16_t _oops_size;
244 #if INCLUDE_JVMCI
245 uint16_t _jvmci_data_size;
246 #endif
247
248 // Offset in immutable data section
249 // _dependencies_offset == 0
250 uint16_t _nul_chk_table_offset;
251 uint16_t _handler_table_offset; // This table could be big in C1 code
252 int _scopes_pcs_offset;
253 int _scopes_data_offset;
254 #if INCLUDE_JVMCI
255 int _speculations_offset;
256 #endif
257
258 // location in frame (offset for sp) that deopt can store the original
259 // pc during a deopt.
260 int _orig_pc_offset;
261
262 int _compile_id; // which compilation made this nmethod
263 CompLevel _comp_level; // compilation level (s1)
264 CompilerType _compiler_type; // which compiler made this nmethod (u1)
265
266 SCCEntry* _scc_entry;
267
268 bool _used; // has this nmethod ever been invoked?
269
270 // Local state used to keep track of whether unloading is happening or not
271 volatile uint8_t _is_unloading_state;
272
273 // Protected by NMethodState_lock
274 volatile signed char _state; // {not_installed, in_use, not_entrant}
275
276 // set during construction
277 uint8_t _has_unsafe_access:1, // May fault due to unsafe access.
278 _has_method_handle_invokes:1,// Has this method MethodHandle invokes?
279 _has_wide_vectors:1, // Preserve wide vectors at safepoints
280 _has_monitors:1, // Fastpath monitor detection for continuations
281 _has_scoped_access:1, // used by for shared scope closure (scopedMemoryAccess.cpp)
282 _has_flushed_dependencies:1, // Used for maintenance of dependencies (under CodeCache_lock)
283 _is_unlinked:1, // mark during class unloading
284 _load_reported:1, // used by jvmti to track if an event has been posted for this nmethod
285 _preloaded:1,
286 _has_clinit_barriers:1;
287
288 enum DeoptimizationStatus : u1 {
289 not_marked,
290 deoptimize,
291 deoptimize_noupdate,
292 deoptimize_done
293 };
294
295 volatile DeoptimizationStatus _deoptimization_status; // Used for stack deoptimization
296
297 DeoptimizationStatus deoptimization_status() const {
298 return Atomic::load(&_deoptimization_status);
299 }
300
301 // Initialize fields to their default values
302 void init_defaults(CodeBuffer *code_buffer, CodeOffsets* offsets);
303
304 // Post initialization
305 void post_init();
306
307 // For native wrappers
308 nmethod(Method* method,
309 CompilerType type,
310 int nmethod_size,
311 int compile_id,
312 CodeOffsets* offsets,
313 CodeBuffer *code_buffer,
314 int frame_size,
315 ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */
316 ByteSize basic_lock_sp_offset, /* synchronized natives only */
317 OopMapSet* oop_maps,
318 int mutable_data_size);
319
320 // For normal JIT compiled code
321 nmethod(Method* method,
322 CompilerType type,
323 int nmethod_size,
324 int immutable_data_size,
325 int mutable_data_size,
326 int compile_id,
327 int entry_bci,
328 address immutable_data,
329 CodeOffsets* offsets,
330 int orig_pc_offset,
331 DebugInformationRecorder *recorder,
332 Dependencies* dependencies,
333 CodeBuffer *code_buffer,
334 int frame_size,
335 OopMapSet* oop_maps,
336 ExceptionHandlerTable* handler_table,
337 ImplicitExceptionTable* nul_chk_table,
338 AbstractCompiler* compiler,
339 CompLevel comp_level
340 , SCCEntry* scc_entry
341 #if INCLUDE_JVMCI
342 , char* speculations = nullptr,
343 int speculations_len = 0,
344 JVMCINMethodData* jvmci_data = nullptr
345 #endif
346 );
347
348 // helper methods
349 void* operator new(size_t size, int nmethod_size, int comp_level) throw();
350
351 // For method handle intrinsics: Try MethodNonProfiled, MethodProfiled and NonNMethod.
352 // Attention: Only allow NonNMethod space for special nmethods which don't need to be
353 // findable by nmethod iterators! In particular, they must not contain oops!
354 void* operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw();
355
356 const char* reloc_string_for(u_char* begin, u_char* end);
357
358 bool try_transition(signed char new_state);
359
360 // Returns true if this thread changed the state of the nmethod or
361 // false if another thread performed the transition.
362 bool make_entrant() { Unimplemented(); return false; }
363 void inc_decompile_count();
364
365 // Inform external interfaces that a compiled method has been unloaded
366 void post_compiled_method_unload();
367
368 PcDesc* find_pc_desc(address pc, bool approximate) {
369 if (_pc_desc_container == nullptr) return nullptr; // native method
370 return _pc_desc_container->find_pc_desc(pc, approximate, code_begin(), scopes_pcs_begin(), scopes_pcs_end());
371 }
372
373 // STW two-phase nmethod root processing helpers.
374 //
375 // When determining liveness of a given nmethod to do code cache unloading,
376 // some collectors need to do different things depending on whether the nmethods
377 // need to absolutely be kept alive during root processing; "strong"ly reachable
378 // nmethods are known to be kept alive at root processing, but the liveness of
379 // "weak"ly reachable ones is to be determined later.
380 //
381 // We want to allow strong and weak processing of nmethods by different threads
382 // at the same time without heavy synchronization. Additional constraints are
383 // to make sure that every nmethod is processed a minimal amount of time, and
384 // nmethods themselves are always iterated at most once at a particular time.
385 //
386 // Note that strong processing work must be a superset of weak processing work
387 // for this code to work.
388 //
389 // We store state and claim information in the _oops_do_mark_link member, using
390 // the two LSBs for the state and the remaining upper bits for linking together
391 // nmethods that were already visited.
392 // The last element is self-looped, i.e. points to itself to avoid some special
393 // "end-of-list" sentinel value.
394 //
395 // _oops_do_mark_link special values:
396 //
397 // _oops_do_mark_link == nullptr: the nmethod has not been visited at all yet, i.e.
398 // is Unclaimed.
399 //
400 // For other values, its lowest two bits indicate the following states of the nmethod:
401 //
402 // weak_request (WR): the nmethod has been claimed by a thread for weak processing
403 // weak_done (WD): weak processing has been completed for this nmethod.
404 // strong_request (SR): the nmethod has been found to need strong processing while
405 // being weak processed.
406 // strong_done (SD): strong processing has been completed for this nmethod .
407 //
408 // The following shows the _only_ possible progressions of the _oops_do_mark_link
409 // pointer.
410 //
411 // Given
412 // N as the nmethod
413 // X the current next value of _oops_do_mark_link
414 //
415 // Unclaimed (C)-> N|WR (C)-> X|WD: the nmethod has been processed weakly by
416 // a single thread.
417 // Unclaimed (C)-> N|WR (C)-> X|WD (O)-> X|SD: after weak processing has been
418 // completed (as above) another thread found that the nmethod needs strong
419 // processing after all.
420 // Unclaimed (C)-> N|WR (O)-> N|SR (C)-> X|SD: during weak processing another
421 // thread finds that the nmethod needs strong processing, marks it as such and
422 // terminates. The original thread completes strong processing.
423 // Unclaimed (C)-> N|SD (C)-> X|SD: the nmethod has been processed strongly from
424 // the beginning by a single thread.
425 //
426 // "|" describes the concatenation of bits in _oops_do_mark_link.
427 //
428 // The diagram also describes the threads responsible for changing the nmethod to
429 // the next state by marking the _transition_ with (C) and (O), which mean "current"
430 // and "other" thread respectively.
431 //
432
433 // States used for claiming nmethods during root processing.
434 static const uint claim_weak_request_tag = 0;
435 static const uint claim_weak_done_tag = 1;
436 static const uint claim_strong_request_tag = 2;
437 static const uint claim_strong_done_tag = 3;
438
439 static oops_do_mark_link* mark_link(nmethod* nm, uint tag) {
440 assert(tag <= claim_strong_done_tag, "invalid tag %u", tag);
441 assert(is_aligned(nm, 4), "nmethod pointer must have zero lower two LSB");
442 return (oops_do_mark_link*)(((uintptr_t)nm & ~0x3) | tag);
443 }
444
445 static uint extract_state(oops_do_mark_link* link) {
446 return (uint)((uintptr_t)link & 0x3);
447 }
448
449 static nmethod* extract_nmethod(oops_do_mark_link* link) {
450 return (nmethod*)((uintptr_t)link & ~0x3);
451 }
452
453 void oops_do_log_change(const char* state);
454
455 static bool oops_do_has_weak_request(oops_do_mark_link* next) {
456 return extract_state(next) == claim_weak_request_tag;
457 }
458
459 static bool oops_do_has_any_strong_state(oops_do_mark_link* next) {
460 return extract_state(next) >= claim_strong_request_tag;
461 }
462
463 // Attempt Unclaimed -> N|WR transition. Returns true if successful.
464 bool oops_do_try_claim_weak_request();
465
466 // Attempt Unclaimed -> N|SD transition. Returns the current link.
467 oops_do_mark_link* oops_do_try_claim_strong_done();
468 // Attempt N|WR -> X|WD transition. Returns nullptr if successful, X otherwise.
469 nmethod* oops_do_try_add_to_list_as_weak_done();
470
471 // Attempt X|WD -> N|SR transition. Returns the current link.
472 oops_do_mark_link* oops_do_try_add_strong_request(oops_do_mark_link* next);
473 // Attempt X|WD -> X|SD transition. Returns true if successful.
474 bool oops_do_try_claim_weak_done_as_strong_done(oops_do_mark_link* next);
475
476 // Do the N|SD -> X|SD transition.
477 void oops_do_add_to_list_as_strong_done();
478
479 // Sets this nmethod as strongly claimed (as part of N|SD -> X|SD and N|SR -> X|SD
480 // transitions).
481 void oops_do_set_strong_done(nmethod* old_head);
482
483 void record_nmethod_dependency();
484
485 void restore_from_archive(nmethod* archived_nm,
486 const methodHandle& method,
487 int compile_id,
488 address reloc_data,
489 GrowableArray<Handle>& oop_list,
490 GrowableArray<Metadata*>& metadata_list,
491 ImmutableOopMapSet* oop_maps,
492 address immutable_data,
493 GrowableArray<Handle>& reloc_imm_oop_list,
494 GrowableArray<Metadata*>& reloc_imm_metadata_list,
495 #ifndef PRODUCT
496 AsmRemarks& asm_remarks,
497 DbgStrings& dbg_strings,
498 #endif /* PRODUCT */
499 SCCReader* scc_reader);
500
501 public:
502 // create nmethod using archived nmethod from AOT code cache
503 static nmethod* new_nmethod(nmethod* archived_nm,
504 const methodHandle& method,
505 AbstractCompiler* compiler,
506 int compile_id,
507 address reloc_data,
508 GrowableArray<Handle>& oop_list,
509 GrowableArray<Metadata*>& metadata_list,
510 ImmutableOopMapSet* oop_maps,
511 address immutable_data,
512 GrowableArray<Handle>& reloc_imm_oop_list,
513 GrowableArray<Metadata*>& reloc_imm_metadata_list,
514 #ifndef PRODUCT
515 AsmRemarks& asm_remarks,
516 DbgStrings& dbg_strings,
517 #endif /* PRODUCT */
518 SCCReader* scc_reader);
519
520 // create nmethod with entry_bci
521 static nmethod* new_nmethod(const methodHandle& method,
522 int compile_id,
523 int entry_bci,
524 CodeOffsets* offsets,
525 int orig_pc_offset,
526 DebugInformationRecorder* recorder,
527 Dependencies* dependencies,
528 CodeBuffer *code_buffer,
529 int frame_size,
530 OopMapSet* oop_maps,
531 ExceptionHandlerTable* handler_table,
532 ImplicitExceptionTable* nul_chk_table,
533 AbstractCompiler* compiler,
534 CompLevel comp_level
535 , SCCEntry* scc_entry
536 #if INCLUDE_JVMCI
537 , char* speculations = nullptr,
538 int speculations_len = 0,
539 JVMCINMethodData* jvmci_data = nullptr
540 #endif
541 );
542
543 static nmethod* new_native_nmethod(const methodHandle& method,
544 int compile_id,
545 CodeBuffer *code_buffer,
546 int vep_offset,
547 int frame_complete,
548 int frame_size,
549 ByteSize receiver_sp_offset,
550 ByteSize basic_lock_sp_offset,
551 OopMapSet* oop_maps,
552 int exception_handler = -1);
553
554 void copy_to(address dest) {
555 memcpy(dest, this, size());
556 }
557
558 Method* method () const { return _method; }
559 uint16_t entry_bci () const { return _entry_bci; }
560 bool is_native_method() const { return _method != nullptr && _method->is_native(); }
561 bool is_java_method () const { return _method != nullptr && !_method->is_native(); }
562 bool is_osr_method () const { return _entry_bci != InvocationEntryBci; }
563
564 // Compiler task identification. Note that all OSR methods
565 // are numbered in an independent sequence if CICountOSR is true,
566 // and native method wrappers are also numbered independently if
567 // CICountNative is true.
568 int compile_id() const { return _compile_id; }
569 const char* compile_kind() const;
570
571 inline bool is_compiled_by_c1 () const { return _compiler_type == compiler_c1; }
572 inline bool is_compiled_by_c2 () const { return _compiler_type == compiler_c2; }
573 inline bool is_compiled_by_jvmci() const { return _compiler_type == compiler_jvmci; }
574 CompilerType compiler_type () const { return _compiler_type; }
575 const char* compiler_name () const;
576
577 // boundaries for different parts
578 address consts_begin () const { return content_begin(); }
579 address consts_end () const { return code_begin() ; }
580 address insts_begin () const { return code_begin() ; }
581 address insts_end () const { return header_begin() + _stub_offset ; }
582 address stub_begin () const { return header_begin() + _stub_offset ; }
583 address stub_end () const { return code_end() ; }
584 address exception_begin () const { return header_begin() + _exception_offset ; }
585 address deopt_handler_begin () const { return header_begin() + _deopt_handler_offset ; }
586 address deopt_mh_handler_begin() const { return _deopt_mh_handler_offset != -1 ? (header_begin() + _deopt_mh_handler_offset) : nullptr; }
587 address unwind_handler_begin () const { return _unwind_handler_offset != -1 ? (insts_end() - _unwind_handler_offset) : nullptr; }
588 oop* oops_begin () const { return (oop*) data_begin(); }
589 oop* oops_end () const { return (oop*) data_end(); }
590
591 // mutable data
592 Metadata** metadata_begin () const { return (Metadata**) (mutable_data_begin() + _relocation_size); }
593 #if INCLUDE_JVMCI
594 Metadata** metadata_end () const { return (Metadata**) (mutable_data_end() - _jvmci_data_size); }
595 address jvmci_data_begin () const { return mutable_data_end() - _jvmci_data_size; }
596 address jvmci_data_end () const { return mutable_data_end(); }
597 #else
598 Metadata** metadata_end () const { return (Metadata**) mutable_data_end(); }
599 #endif
600
601 // immutable data
602 void set_immutable_data(address data) { _immutable_data = data; }
603 address immutable_data_begin () const { return _immutable_data; }
604 address immutable_data_end () const { return _immutable_data + _immutable_data_size ; }
605 address dependencies_begin () const { return _immutable_data; }
606 address dependencies_end () const { return _immutable_data + _nul_chk_table_offset; }
607 address nul_chk_table_begin () const { return _immutable_data + _nul_chk_table_offset; }
608 address nul_chk_table_end () const { return _immutable_data + _handler_table_offset; }
609 address handler_table_begin () const { return _immutable_data + _handler_table_offset; }
610 address handler_table_end () const { return _immutable_data + _scopes_pcs_offset ; }
611 PcDesc* scopes_pcs_begin () const { return (PcDesc*)(_immutable_data + _scopes_pcs_offset) ; }
612 PcDesc* scopes_pcs_end () const { return (PcDesc*)(_immutable_data + _scopes_data_offset) ; }
613 address scopes_data_begin () const { return _immutable_data + _scopes_data_offset ; }
614
615 #if INCLUDE_JVMCI
616 address scopes_data_end () const { return _immutable_data + _speculations_offset ; }
617 address speculations_begin () const { return _immutable_data + _speculations_offset ; }
618 address speculations_end () const { return immutable_data_end(); }
619 #else
620 address scopes_data_end () const { return immutable_data_end(); }
621 #endif
622
623 // Sizes
624 int immutable_data_size() const { return _immutable_data_size; }
625 int consts_size () const { return int( consts_end () - consts_begin ()); }
626 int insts_size () const { return int( insts_end () - insts_begin ()); }
627 int stub_size () const { return int( stub_end () - stub_begin ()); }
628 int oops_size () const { return int((address) oops_end () - (address) oops_begin ()); }
629 int metadata_size () const { return int((address) metadata_end () - (address) metadata_begin ()); }
630 int scopes_data_size () const { return int( scopes_data_end () - scopes_data_begin ()); }
631 int scopes_pcs_size () const { return int((intptr_t)scopes_pcs_end () - (intptr_t)scopes_pcs_begin ()); }
632 int dependencies_size () const { return int( dependencies_end () - dependencies_begin ()); }
633 int handler_table_size () const { return int( handler_table_end() - handler_table_begin()); }
634 int nul_chk_table_size () const { return int( nul_chk_table_end() - nul_chk_table_begin()); }
635 #if INCLUDE_JVMCI
636 int speculations_size () const { return int( speculations_end () - speculations_begin ()); }
637 int jvmci_data_size () const { return int( jvmci_data_end () - jvmci_data_begin ()); }
638 #endif
639
640 int oops_count() const { assert(oops_size() % oopSize == 0, ""); return (oops_size() / oopSize) + 1; }
641 int metadata_count() const { assert(metadata_size() % wordSize == 0, ""); return (metadata_size() / wordSize) + 1; }
642
643 int skipped_instructions_size () const { return _skipped_instructions_size; }
644 int total_size() const;
645
646 // Containment
647 bool consts_contains (address addr) const { return consts_begin () <= addr && addr < consts_end (); }
648 // Returns true if a given address is in the 'insts' section. The method
649 // insts_contains_inclusive() is end-inclusive.
650 bool insts_contains (address addr) const { return insts_begin () <= addr && addr < insts_end (); }
651 bool insts_contains_inclusive(address addr) const { return insts_begin () <= addr && addr <= insts_end (); }
652 bool stub_contains (address addr) const { return stub_begin () <= addr && addr < stub_end (); }
653 bool oops_contains (oop* addr) const { return oops_begin () <= addr && addr < oops_end (); }
654 bool metadata_contains (Metadata** addr) const { return metadata_begin () <= addr && addr < metadata_end (); }
655 bool scopes_data_contains (address addr) const { return scopes_data_begin () <= addr && addr < scopes_data_end (); }
656 bool scopes_pcs_contains (PcDesc* addr) const { return scopes_pcs_begin () <= addr && addr < scopes_pcs_end (); }
657 bool handler_table_contains (address addr) const { return handler_table_begin() <= addr && addr < handler_table_end(); }
658 bool nul_chk_table_contains (address addr) const { return nul_chk_table_begin() <= addr && addr < nul_chk_table_end(); }
659
660 // entry points
661 address entry_point() const { return code_begin() + _entry_offset; } // normal entry point
662 address verified_entry_point() const { return code_begin() + _verified_entry_offset; } // if klass is correct
663
664 enum : signed char { not_installed = -1, // in construction, only the owner doing the construction is
665 // allowed to advance state
666 in_use = 0, // executable nmethod
667 not_entrant = 1 // marked for deoptimization but activations may still exist
668 };
669
670 // flag accessing and manipulation
671 bool is_not_installed() const { return _state == not_installed; }
672 bool is_in_use() const { return _state <= in_use; }
673 bool is_not_entrant() const { return _state == not_entrant; }
674 int get_state() const { return _state; }
675
676 void clear_unloading_state();
677 // Heuristically deduce an nmethod isn't worth keeping around
678 bool is_cold();
679 bool is_unloading();
680 void do_unloading(bool unloading_occurred);
681
682 void inc_method_profiling_count();
683 uint64_t method_profiling_count();
684
685 bool make_in_use() {
686 return try_transition(in_use);
687 }
688 // Make the nmethod non entrant. The nmethod will continue to be
689 // alive. It is used when an uncommon trap happens. Returns true
690 // if this thread changed the state of the nmethod or false if
691 // another thread performed the transition.
692 bool make_not_entrant(const char* reason, bool make_not_entrant = true);
693 bool make_not_used() { return make_not_entrant("not used"); }
694
695 bool is_marked_for_deoptimization() const { return deoptimization_status() != not_marked; }
696 bool has_been_deoptimized() const { return deoptimization_status() == deoptimize_done; }
697 void set_deoptimized_done();
698
699 bool update_recompile_counts() const {
700 // Update recompile counts when either the update is explicitly requested (deoptimize)
701 // or the nmethod is not marked for deoptimization at all (not_marked).
702 // The latter happens during uncommon traps when deoptimized nmethod is made not entrant.
703 DeoptimizationStatus status = deoptimization_status();
704 return status != deoptimize_noupdate && status != deoptimize_done;
705 }
706
707 // tells whether frames described by this nmethod can be deoptimized
708 // note: native wrappers cannot be deoptimized.
709 bool can_be_deoptimized() const { return is_java_method(); }
710
711 bool has_dependencies() { return dependencies_size() != 0; }
712 void print_dependencies_on(outputStream* out) PRODUCT_RETURN;
713 void flush_dependencies();
714
715 template<typename T>
716 T* gc_data() const { return reinterpret_cast<T*>(_gc_data); }
717 template<typename T>
718 void set_gc_data(T* gc_data) { _gc_data = reinterpret_cast<void*>(gc_data); }
719
720 bool has_unsafe_access() const { return _has_unsafe_access; }
721 void set_has_unsafe_access(bool z) { _has_unsafe_access = z; }
722
723 bool has_monitors() const { return _has_monitors; }
724 void set_has_monitors(bool z) { _has_monitors = z; }
725
726 bool has_scoped_access() const { return _has_scoped_access; }
727 void set_has_scoped_access(bool z) { _has_scoped_access = z; }
728
729 bool has_method_handle_invokes() const { return _has_method_handle_invokes; }
730 void set_has_method_handle_invokes(bool z) { _has_method_handle_invokes = z; }
731
732 bool has_wide_vectors() const { return _has_wide_vectors; }
733 void set_has_wide_vectors(bool z) { _has_wide_vectors = z; }
734
735 bool has_clinit_barriers() const { return _has_clinit_barriers; }
736 void set_has_clinit_barriers(bool z) { _has_clinit_barriers = z; }
737
738 bool preloaded() const { return _preloaded; }
739 void set_preloaded(bool z) { _preloaded = z; }
740
741 bool has_flushed_dependencies() const { return _has_flushed_dependencies; }
742 void set_has_flushed_dependencies(bool z) {
743 assert(!has_flushed_dependencies(), "should only happen once");
744 _has_flushed_dependencies = z;
745 }
746
747 bool is_unlinked() const { return _is_unlinked; }
748 void set_is_unlinked() {
749 assert(!_is_unlinked, "already unlinked");
750 _is_unlinked = true;
751 }
752
753 int comp_level() const { return _comp_level; }
754
755 // Support for oops in scopes and relocs:
756 // Note: index 0 is reserved for null.
757 oop oop_at(int index) const;
758 oop oop_at_phantom(int index) const; // phantom reference
759 oop* oop_addr_at(int index) const { // for GC
760 // relocation indexes are biased by 1 (because 0 is reserved)
761 assert(index > 0 && index <= oops_count(), "must be a valid non-zero index");
762 return &oops_begin()[index - 1];
763 }
764
765 // Support for meta data in scopes and relocs:
766 // Note: index 0 is reserved for null.
767 Metadata* metadata_at(int index) const { return index == 0 ? nullptr: *metadata_addr_at(index); }
768 Metadata** metadata_addr_at(int index) const { // for GC
769 // relocation indexes are biased by 1 (because 0 is reserved)
770 assert(index > 0 && index <= metadata_count(), "must be a valid non-zero index");
771 return &metadata_begin()[index - 1];
772 }
773
774 void copy_values(GrowableArray<Handle>* array);
775 void copy_values(GrowableArray<jobject>* oops);
776 void copy_values(GrowableArray<Metadata*>* metadata);
777 void copy_values(GrowableArray<address>* metadata) {} // Nothing to do
778
779 // Relocation support
780 private:
781 void fix_oop_relocations(address begin, address end, bool initialize_immediates);
782 inline void initialize_immediate_oop(oop* dest, jobject handle);
783
784 protected:
785 address oops_reloc_begin() const;
786
787 public:
788 void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); }
789 void fix_oop_relocations() { fix_oop_relocations(nullptr, nullptr, false); }
790
791 void create_reloc_immediates_list(JavaThread* thread, GrowableArray<Handle>& oop_list, GrowableArray<Metadata*>& metadata_list);
792
793 bool is_at_poll_return(address pc);
794 bool is_at_poll_or_poll_return(address pc);
795
796 protected:
797 // Exception cache support
798 // Note: _exception_cache may be read and cleaned concurrently.
799 ExceptionCache* exception_cache() const { return _exception_cache; }
800 ExceptionCache* exception_cache_acquire() const;
801
802 public:
803 address handler_for_exception_and_pc(Handle exception, address pc);
804 void add_handler_for_exception_and_pc(Handle exception, address pc, address handler);
805 void clean_exception_cache();
806
807 void add_exception_cache_entry(ExceptionCache* new_entry);
808 ExceptionCache* exception_cache_entry_for_exception(Handle exception);
809
810
811 // MethodHandle
812 bool is_method_handle_return(address return_pc);
813 // Deopt
814 // Return true is the PC is one would expect if the frame is being deopted.
815 inline bool is_deopt_pc(address pc);
816 inline bool is_deopt_mh_entry(address pc);
817 inline bool is_deopt_entry(address pc);
818
819 // Accessor/mutator for the original pc of a frame before a frame was deopted.
820 address get_original_pc(const frame* fr) { return *orig_pc_addr(fr); }
821 void set_original_pc(const frame* fr, address pc) { *orig_pc_addr(fr) = pc; }
822
823 const char* state() const;
824
825 bool inlinecache_check_contains(address addr) const {
826 return (addr >= code_begin() && addr < verified_entry_point());
827 }
828
829 void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f);
830
831 // implicit exceptions support
832 address continuation_for_implicit_div0_exception(address pc) { return continuation_for_implicit_exception(pc, true); }
833 address continuation_for_implicit_null_exception(address pc) { return continuation_for_implicit_exception(pc, false); }
834
835 // Inline cache support for class unloading and nmethod unloading
836 private:
837 void cleanup_inline_caches_impl(bool unloading_occurred, bool clean_all);
838
839 address continuation_for_implicit_exception(address pc, bool for_div0_check);
840
841 public:
842 // Serial version used by whitebox test
843 void cleanup_inline_caches_whitebox();
844
845 void clear_inline_caches();
846
847 // Execute nmethod barrier code, as if entering through nmethod call.
848 void run_nmethod_entry_barrier();
849
850 void verify_oop_relocations();
851
852 bool has_evol_metadata();
853
854 Method* attached_method(address call_pc);
855 Method* attached_method_before_pc(address pc);
856
857 // GC unloading support
858 // Cleans unloaded klasses and unloaded nmethods in inline caches
859
860 void unload_nmethod_caches(bool class_unloading_occurred);
861
862 void unlink_from_method();
863
864 // On-stack replacement support
865 int osr_entry_bci() const { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; }
866 address osr_entry() const { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; }
867 nmethod* osr_link() const { return _osr_link; }
868 void set_osr_link(nmethod *n) { _osr_link = n; }
869 void invalidate_osr_method();
870
871 int num_stack_arg_slots(bool rounded = true) const {
872 return rounded ? align_up(_num_stack_arg_slots, 2) : _num_stack_arg_slots;
873 }
874
875 // Verify calls to dead methods have been cleaned.
876 void verify_clean_inline_caches();
877
878 // Unlink this nmethod from the system
879 void unlink();
880
881 // Deallocate this nmethod - called by the GC
882 void purge(bool unregister_nmethod);
883
884 // See comment at definition of _last_seen_on_stack
885 void mark_as_maybe_on_stack();
886 bool is_maybe_on_stack();
887
888 // Evolution support. We make old (discarded) compiled methods point to new Method*s.
889 void set_method(Method* method) { _method = method; }
890
891 #if INCLUDE_JVMCI
892 // Gets the JVMCI name of this nmethod.
893 const char* jvmci_name();
894
895 // Records the pending failed speculation in the
896 // JVMCI speculation log associated with this nmethod.
897 void update_speculation(JavaThread* thread);
898
899 // Gets the data specific to a JVMCI compiled method.
900 // This returns a non-nullptr value iff this nmethod was
901 // compiled by the JVMCI compiler.
902 JVMCINMethodData* jvmci_nmethod_data() const {
903 return jvmci_data_size() == 0 ? nullptr : (JVMCINMethodData*) jvmci_data_begin();
904 }
905 #endif
906
907 void oops_do(OopClosure* f) { oops_do(f, false); }
908 void oops_do(OopClosure* f, bool allow_dead);
909
910 // All-in-one claiming of nmethods: returns true if the caller successfully claimed that
911 // nmethod.
912 bool oops_do_try_claim();
913
914 // Loom support for following nmethods on the stack
915 void follow_nmethod(OopIterateClosure* cl);
916
917 // Class containing callbacks for the oops_do_process_weak/strong() methods
918 // below.
919 class OopsDoProcessor {
920 public:
921 // Process the oops of the given nmethod based on whether it has been called
922 // in a weak or strong processing context, i.e. apply either weak or strong
923 // work on it.
924 virtual void do_regular_processing(nmethod* nm) = 0;
925 // Assuming that the oops of the given nmethod has already been its weak
926 // processing applied, apply the remaining strong processing part.
927 virtual void do_remaining_strong_processing(nmethod* nm) = 0;
928 };
929
930 // The following two methods do the work corresponding to weak/strong nmethod
931 // processing.
932 void oops_do_process_weak(OopsDoProcessor* p);
933 void oops_do_process_strong(OopsDoProcessor* p);
934
935 static void oops_do_marking_prologue();
936 static void oops_do_marking_epilogue();
937
938 private:
939 ScopeDesc* scope_desc_in(address begin, address end);
940
941 address* orig_pc_addr(const frame* fr);
942
943 // used by jvmti to track if the load events has been reported
944 bool load_reported() const { return _load_reported; }
945 void set_load_reported() { _load_reported = true; }
946
947 public:
948 // ScopeDesc retrieval operation
949 PcDesc* pc_desc_at(address pc) { return find_pc_desc(pc, false); }
950 // pc_desc_near returns the first PcDesc at or after the given pc.
951 PcDesc* pc_desc_near(address pc) { return find_pc_desc(pc, true); }
952
953 // ScopeDesc for an instruction
954 ScopeDesc* scope_desc_at(address pc);
955 ScopeDesc* scope_desc_near(address pc);
956
957 // copying of debugging information
958 void copy_scopes_pcs(PcDesc* pcs, int count);
959 void copy_scopes_data(address buffer, int size);
960
961 int orig_pc_offset() { return _orig_pc_offset; }
962
963 SCCEntry* scc_entry() const { return _scc_entry; }
964 bool is_scc() const { return scc_entry() != nullptr; }
965 void set_scc_entry(SCCEntry* entry) { _scc_entry = entry; }
966
967 bool used() const { return _used; }
968 void set_used() { _used = true; }
969
970 // Post successful compilation
971 void post_compiled_method(CompileTask* task);
972
973 // jvmti support:
974 void post_compiled_method_load_event(JvmtiThreadState* state = nullptr);
975
976 // verify operations
977 void verify();
978 void verify_scopes();
979 void verify_interrupt_point(address interrupt_point, bool is_inline_cache);
980
981 // Disassemble this nmethod with additional debug information, e.g. information about blocks.
982 void decode2(outputStream* st) const;
983 void print_constant_pool(outputStream* st);
984
985 // Avoid hiding of parent's 'decode(outputStream*)' method.
986 void decode(outputStream* st) const { decode2(st); } // just delegate here.
987
988 // printing support
989 void print_on_impl(outputStream* st) const;
990 void print_code();
991 void print_value_on_impl(outputStream* st) const;
992
993 #if defined(SUPPORT_DATA_STRUCTS)
994 // print output in opt build for disassembler library
995 void print_relocations_on(outputStream* st) PRODUCT_RETURN;
996 void print_pcs_on(outputStream* st);
997 void print_scopes() { print_scopes_on(tty); }
998 void print_scopes_on(outputStream* st) PRODUCT_RETURN;
999 void print_handler_table();
1000 void print_nul_chk_table();
1001 void print_recorded_oop(int log_n, int index);
1002 void print_recorded_oops();
1003 void print_recorded_metadata();
1004
1005 void print_oops(outputStream* st); // oops from the underlying CodeBlob.
1006 void print_metadata(outputStream* st); // metadata in metadata pool.
1007 #else
1008 void print_pcs_on(outputStream* st) { return; }
1009 #endif
1010
1011 void print_calls(outputStream* st) PRODUCT_RETURN;
1012 static void print_statistics() PRODUCT_RETURN;
1013
1014 void maybe_print_nmethod(const DirectiveSet* directive);
1015 void print_nmethod(bool print_code);
1016
1017 void print_on_with_msg(outputStream* st, const char* msg) const;
1018
1019 // Logging
1020 void log_identity(xmlStream* log) const;
1021 void log_new_nmethod() const;
1022 void log_state_change(const char* reason) const;
1023
1024 // Prints block-level comments, including nmethod specific block labels:
1025 void print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels=true) const;
1026 const char* nmethod_section_label(address pos) const;
1027
1028 // returns whether this nmethod has code comments.
1029 bool has_code_comment(address begin, address end);
1030 // Prints a comment for one native instruction (reloc info, pc desc)
1031 void print_code_comment_on(outputStream* st, int column, address begin, address end);
1032
1033 // tells if this compiled method is dependent on the given changes,
1034 // and the changes have invalidated it
1035 bool check_dependency_on(DepChange& changes);
1036
1037 // Fast breakpoint support. Tells if this compiled method is
1038 // dependent on the given method. Returns true if this nmethod
1039 // corresponds to the given method as well.
1040 bool is_dependent_on_method(Method* dependee);
1041
1042 // JVMTI's GetLocalInstance() support
1043 ByteSize native_receiver_sp_offset() {
1044 assert(is_native_method(), "sanity");
1045 return _native_receiver_sp_offset;
1046 }
1047 ByteSize native_basic_lock_sp_offset() {
1048 assert(is_native_method(), "sanity");
1049 return _native_basic_lock_sp_offset;
1050 }
1051
1052 // support for code generation
1053 static ByteSize osr_entry_point_offset() { return byte_offset_of(nmethod, _osr_entry_point); }
1054 static ByteSize state_offset() { return byte_offset_of(nmethod, _state); }
1055
1056 void metadata_do(MetadataClosure* f);
1057
1058 address call_instruction_address(address pc) const;
1059
1060 void make_deoptimized();
1061 void finalize_relocations();
1062
1063 void prepare_for_archiving();
1064
1065 class Vptr : public CodeBlob::Vptr {
1066 void print_on(const CodeBlob* instance, outputStream* st) const override {
1067 ttyLocker ttyl;
1068 instance->as_nmethod()->print_on_impl(st);
1069 }
1070 void print_value_on(const CodeBlob* instance, outputStream* st) const override {
1071 instance->as_nmethod()->print_value_on_impl(st);
1072 }
1073 };
1074
1075 static const Vptr _vpntr;
1076 };
1077
1078 #endif // SHARE_CODE_NMETHOD_HPP